The present invention relates to a switching power supply device, a semiconductor integrated circuit device, and a power supply device. For instance, the present invention relates to a technique effective to be applied to a switching power supply device converting a high voltage to a low voltage and a semiconductor integrated circuit device used therefor.
There is U.S. Pat. No. 6,559,684 as a switching power supply device. There is “Fundamentals of Power Electronics Second Edition”, pp. 439-449, published by KLUWER ACADEMIC PUBLISHERS in the United States, as a technical document related to a switching power supply device.    [Patent Document 1] U.S. Pat. No. 6,559,684    [Non-Patent Document 1] “Fundamentals of Power Electronics Second Edition”, pp. 439-449, published by KLUWER ACADEMIC PUBLISHERS